These cells, grown from skin cells taken from people with bipolar disorder, arose from stem cells and were coaxed to become neural progenitor cells -- the kind that can become any sort of nervous system cell. The research showed differences in cell behavior compared with cells grown from people without bipolar disorder.

Stem Cells Shed Light on Bipolar Disorder

By Maggie Fox

Researchers have grown embryonic-like stem cells from patients with bipolar disorder and transformed them into brain cells that are already answering questions about the condition.

The cells, which carry the precisely tailored genetic instructions from the patients’ own cells, behave differently than cells taken from people without the disorder, the researchers report.

“Already, we see that cells from people with bipolar disorder are different in how often they express certain genes, how they differentiate into neurons, how they communicate, and how they respond to lithium," Sue O'Shea, a stem cell specialist at the University of Michigan who led the study, said in a statement.

The work, described in the journal Translational Psychiatry, helps fulfill one of the big promises of stem cells research – using a patient’s own cells to study his or her disease.

Mental illness is especially hard to study. Getting into a living person’s brain is almost impossible, and scientists can’t deliberately cause it in people in order to study it.

Creating animals such as mice with what looks like human mental illness is imprecise at best.

The University of Michigan team turned instead to what are called induced pluripotent stem cells, or iPS cells. These are ordinary skin cells taken from a patient and tricked into turning back into the state of a just-conceived embryo.

University of Michigan Pluripotent Stem Cell Research Lab

These cells, grown from skin cells taken from people with bipolar disorder, arose from stem cells and were coaxed to become neural progenitor cells -- the kind that can become any sort of nervous system cell. The research showed differences in cell behavior compared with cells grown from people without bipolar disorder.

They are pluripotent, meaning they can become any type of cell there is. In this case, the Michigan team redirected the cells to become neurons – the cells that make up much of the brain. "This gives us a model that we can use to examine how cells behave as they develop into neurons,” O’Shea said.

Bipolar disorder, once called manic-depression, is very common, affecting an estimated 3 percent of the population globally. It runs in families, suggesting a strong genetic cause, and is marked by mood swings from depression to feelings of euphoria and creativity that’s considered the manic phase.

Half of cases develop before a person turns 25, according to the National Institute on Mental Health. There are many different treatments, including lithium, antidepressants and antipsychotics. But treatment is usually hit and miss and doctors would like better ways of predicting which drugs will work best in different patients.

Having a batch of human brain cells in a lab dish would also offer better ways to test new drugs, the researchers say.

Maggie Fox

She's a former managing editor for healthcare and technology at National Journal and global health and science editor for Reuters based in Washington, D.C. and London.

She's reported for news agencies, radio, newspapers, magazines and television from across Asia, the Middle East, Africa and Europe covering news ranging from war to politics and, of course, health and science. Her reporting has taken Maggie to Lebanon, Syria and Libya; to China, South Korea, Thailand, the Philippines and Pakistan; to Bosnia, Croatia and Serbia and to Ireland and Northern Ireland and across the rest of Europe.

Maggie has won awards from the Society of Business Editors and Writers, the National Immunization Program, the Overseas Press Club and other organizations. She's done fellowships at Harvard Medical School, the National Institutes of Health and the University of Maryland.